var captcha_img = $('#captcha-container').find('img')
var verifyimg = captcha_img.attr("src");
captcha_img.attr('title', '点击刷新');
captcha_img.click(function () {
    if (verifyimg.indexOf('?') > 0) {
        $(this).attr("src", verifyimg + '&random=' + Math.random());
    } else {
        $(this).attr("src", verifyimg.replace(/\?.*$/, '') + '?' + Math.random());
    }
});